Solar energy collection conduit

ABSTRACT

A solar energy collection conduit ( 10 ) comprising an optical concentrator ( 40 ) incorporated into an outer tube ( 30 ) having a sunlight-transmitting ceiling ( 32 ). The concentrator ( 40 ) focuses, guides, directs, and/or otherwise concentrates sunlight towards a pipe ( 50 ). Fluid ( 60 ) conveyed by the pipe ( 50 ) can be heated to very high temperatures (e.g., up to and above about 100° C., about 200° C., and/or about 300° C.).

RELATED APPLICATION

This application claims priority under 35 USC §119(e) to U.S.Provisional Patent Application No. 61/702,631 filed on Sep. 18, 2012.The entire disclosure of this provisional patent application is herebyincorporated by reference.

BACKGROUND

A tried-and-true solar energy collection conduit comprises an outer tubehaving a wall defining a collection chamber, this chamber-defining wallhaving a ceiling which transmits sunlight therethrough. A pipe resideswithin a sunlight-absorbing region of the collection chamber and conveysfluid therethrough. Reflectors and shields can be strategically placedto maximize heat transfer to the fluid-conveying pipe. And when opticalconcentrating lens are added to the equation, it is possible to heat thefluid to very high temperatures (e.g., up to and above about 100° C.,about 200° C., and/or about 300° C.).

SUMMARY

A solar energy collection conduit is provided wherein an opticalconcentrator is incorporated into the outer tube. In this manner, solarenergy can be focused along the entire length of the fluid-conveyingpipe (as opposed to spaced target areas).

DRAWINGS

FIGS. 1-9 show some possible embodiments of the solar energy collectionconduit and the corresponding FIGS. 1A-9A show sections of therespective conduit.

FIG. 10 shows a plurality of the solar energy collection conduitsconnected in series to form a panel-like cell.

FIGS. 11-14 show the solar energy collection cell as the fluid-heatingcomponent in a power generation system, a water heating system, adesalination system, and a regeneration system.

DESCRIPTION

Referring now to the drawings, and initially to FIG. 1, the solar energycollection conduit 10 comprises a collection chamber 20 including asunlight-absorbing region 21. An outer tube 30 includes a wall 31defining the collection chamber 20 and this chamber-defining wall 31 hasa ceiling 32 which transmits sunlight therethrough. The chamber 20 canbe evacuated and/or it can be filled with a sunlight-absorbing medium.

An optical concentrator 40 is incorporated into the wall 31 of the outertube 30. More particularly, in the embodiment shown in FIG. 1, theoptical concentrator 40 is incorporated into the light-transmittingceiling 32 of the wall 31. The concentrator 40 causes sunlighttransmitted through the ceiling 22 to be directed, focused, or otherwiseconcentrated towards the sunlight-absorbing region 21 of the chamber 20.

The light-transmitting ceiling 32 can preferably extend substantiallythe entire length of the collection chamber 30. And the opticalconcentrator 40 can preferably extend substantially the length of thelight-transmitting ceiling 32.

As only the ceiling 32 need be transparent to sunlight, non-ceilingsections of the wall 31 can be made of a nontransparent material. If thelight-transmitting ceiling 32 is formed in one piece with rest of thechamber-defining wall 31, non-ceiling sections can be made opaque by,for example, painting them black. The chamber-defining wall 31 and/orthe light-transmitting ceiling 32 can be made from acrylic (e.g., PMMA),polycarbonate, and/or traditional glass materials. They can be formed byinjection molding, compression molding, extrusion, machining, or cellcasting.

The solar energy collection conduit 10 can further comprise a pipe 50and a fluid 60 which is conveyed therethrough. The fluid-conveying pipe50 resides in the sunlight-absorbing region 21 of the collection chamber20. The pipe 50 can be made of a metal (e.g., copper), ceramic, or anyother heat-conducting material. The fluid can be water, seawater, oil,refrigerant, or other suitable liquid or gas. Thanks to the opticalconcentrator 40, it is possible to heat the fluid 60 within the pipe 50to very high temperatures (e.g., up to and above about 100° C., about200° C., and/or about 300° C.).

A reflector plate 70 can be positioned to reflect sunlight upwards backinto the sunlight-absorbing region 21 of the collection chamber 20. Inthe illustrated embodiments, for example, the plate 70 is positionedbeneath the fluid-conveying pipe 50. Other reflection and/or refractiondevices can be positioned within the chamber 20. And conduits 10 and/orchambers 20 without such devices are feasible and foreseeable.

Referring additionally to FIG. 1A, the concentrator 40 comprises asubstrate 41 and sunlight-concentrating features 42 formed on thissubstrate 41. The substrate 41 extends downward from the interiorsurface 33 of the ceiling 32 and the features 42 are formed on thesubstrate's lower surface 43. The sunlight-concentrating features 42 inthis embodiment comprise Fresnel prisms.

In the conduit 10 shown in FIG. 2 (and FIG. 2A), thesunlight-concentrating features 42 also comprise Fresnel prisms. But inthis embodiment, the substrate 41 extends upward from an exteriorsurface 34 of the ceiling 32 and the sunlight-concentrating features areformed on the substrate's upper surface 44.

In the conduit 10 shown in FIGS. 3-6, the sunlight-concentratingfeatures 42 comprise meniscus lens (FIGS. 3-4) or they comprisesplanoconvex lens (FIGS. 5-6). The substrate 41 can extend downward fromthe interior surface 33 of the ceiling 32 and the features 42 can beformed on the substrate's lower surface 43 (FIG. 3 and FIG. 5). Or thesubstrate 41 can extend upward from the exterior surface 34 of theceiling 32 and the features 42 can be formed on the substrate's uppersurface 44 (FIG. 4 and FIG. 6).

In the conduit 10 shown in FIGS. 7-9, the substrate 41 is situatedwithin the chamber 20 at a location downward from the ceiling 32 andupward from the sunlight-absorbing region 21. The substrate 41 canextend laterally across the width the wall 31. The solar-concentratingfeatures 42 can comprise Fresnel prisms (FIG. 7), meniscus lens (FIG.8), or planoconvex lens (FIG. 9).

The substrate 41 can be formed in one piece with the chamber-definingwall 31. Alternatively, the substrate 41 can be formed as a separatepiece from the wall 31 and then attached thereto by notching,press-fitting, adhesive, soldering, or other appropriate attachmenttechniques. A further option is to mold or otherwise form the substrate41 onto the wall 31. The features 42 can be formed at the same time asthe rest of the substrate 41 and/or they can be featured thereon duringa latter manufacturing stage.

The substrate 41 can be made of any suitable material which is opticallytransparent, compatible with attachment to the wall 31, and capable ofcarrying the sunlight-concentrating features 42. Acceptable candidatescould include, for example, acrylic, polycarbonate, or glass. Thesubstrate 41 and/or the features 42 can be made by injection molding,compression molding, extrusion, machining, and/or cell casting.

As shown in FIG. 10, a plurality of the solar energy collection conduits10 can be connected in series to form a panel-like cell 80.

And as shown in FIGS. 11-14, this cell 80 can be the fluid-heatingcomponent of a power generation system 91, a water heating system 92, adesalination system 93, or a heat battery reconstitution system 94.

One may now appreciate that a solar energy collection conduit 10 isprovided wherein an optical concentrator 40 is incorporated into theouter tube 30. Although the conduit 10, the chamber 20, the tube 30, theconcentrator 40, the pipe 50, the fluid 60, the plate 70, the cell 80,and/or the systems 91-94 have been shown and described with respect tocertain embodiments, it is obvious that equivalent alterations andmodifications will occur to others skilled in the art upon the readingand understanding of this specification and the annexed drawings.

1. A solar energy collection conduit comprising: a collection chamber including a sunlight-absorbing region, an outer tube having a wall defining the collection chamber, this chamber-defining wall having a ceiling which transmits sunlight therethrough, and an optical concentrator concentrating sunlight transmitted therethrough to the sunlight-absorbing region of the collection chamber; wherein the optical concentrator is incorporated into the outer tube.
 2. A solar energy collection conduit as set forth in claim 1, wherein the optical concentrator extends substantially the length of the light-transmitting ceiling.
 3. A solar energy collection conduit as set forth in claim 1, wherein the light-transmitting ceiling extends substantially the length of the collection chamber.
 4. A solar energy collection conduit as set forth in claim 1, wherein the light-transmitting ceiling is formed in one piece with the rest of the chamber-defining wall.
 5. A solar energy collection conduit as set forth in claim 1, wherein the optical concentrator comprises a substrate and sunlight-concentrating features formed on this substrate.
 6. A solar energy collection conduit as set forth in claim 5, wherein the sunlight-concentrating features comprise Fresnel prisms.
 7. A solar energy collection conduit as set forth in claim 5, wherein the sunlight-concentrating features comprise meniscus lens.
 8. A solar energy collection conduit as set forth in claim 5, wherein the sunlight-concentrating features comprise planoconvex lens.
 9. A solar energy collection conduit as set forth in claim 1, wherein the substrate is attached to the sunlight-transmitting ceiling.
 10. A solar energy collection conduit as set forth in claim 9, wherein the substrate extends downward from an interior surface of the sunlight-transmitting ceiling and the sunlight concentrating features are formed on an upper surface of this substrate.
 11. A solar energy collection conduit as set forth in claim 9, wherein the substrate extends upward from an exterior surface of the sunlight-transmitting ceiling and the sunlight-concentrating features are formed on a lower surface of this substrate.
 12. A solar energy collection conduit as set forth in claim 1, wherein the substrate is situated within the chamber below the light-transmitting ceiling and above the sunlight-absorbing region.
 13. A solar energy collection conduit as set forth in claim 12, wherein the substrate extends across the width of the outer tube.
 14. A solar energy collection conduit as set forth in claim 13, wherein the substrate is formed in one piece with the outer tube.
 15. A solar energy collection conduit as set forth in claim 13, wherein the substrate is formed separate from the outer tube and then bonded thereto.
 16. A solar energy collection conduit as set forth in claim 1, further comprising a fluid-transferring pipe residing within the sunlight-absorbing region of the collection chamber.
 17. A solar energy collection conduit as set forth in claim 16, claims, comprising a fluid being conveyed within the pipe.
 18. A solar energy collection conduit as set forth in claim 17, wherein the fluid is water, seawater, air, refrigerant, or oil.
 19. A solar energy collection cell comprising a plurality of the solar energy collection conduits as set forth in claim 16, wherein the conduits' fluid-conveying pipes are connected in series.
 20. A system comprising the solar energy collection cell set forth in claim 19, wherein the cell is the fluid-heating component, and wherein the system is a power generation system, a water heating system, a desalination system, or a heat battery reconstitution system. 